EP4621823A1

EP4621823A1 - Circuit breaker

Info

Publication number: EP4621823A1
Application number: EP25305395.3A
Authority: EP
Inventors: Qi Li; Zhenzhong Liu; Wenmei Li
Original assignee: Schneider Electric Industries SAS
Current assignee: Schneider Electric Industries SAS
Priority date: 2024-03-22
Filing date: 2025-03-21
Publication date: 2025-09-24
Also published as: CN120690643A

Abstract

A circuit breaker 10 comprises: a main body 100 having a stationary contact 110 and a movable contact, the movable contact being movable to contact with or separate from the stationary contact; a tripping assembly 200 assembled to the main body, the tripping assembly being movable between a normal position and a trigger position, and the tripping assembly triggering the movable contact to separate from the stationary contact when the tripping assembly moves from the normal position to the trigger position; wherein, the tripping assembly has a current sensing part 210 which is located near the stationary contact and is configured to be movable based on the current intensity flowing through the stationary contact.

Description

TECHNICAL FIELD

The invention relates to a circuit breaker, in particular to a circuit breaker with better tripping performance and lower cost.

BACKGROUND

The circuit breaker controls the turn-on and turn-off of the circuit by switching between the closing state and the opening state. If an abnormal condition occurs in the circuit, which leads to current overload, the tripping assembly will trigger the circuit breaker to switch from the closing state to the opening state to protect the circuit in response to excessive current.
In the prior art, current usually flows through the tripping assembly so that the tripping assembly can sense the intensity of current in the circuit in real time to determine whether to trigger the circuit breaker to open based on the intensity of current. However, the current flowing through the tripping assembly requires some parts of the tripping assembly to have high insulation, and the current flowing through the tripping assembly will generate heat in the tripping assembly, which requires some parts of the tripping assembly to have high heat resistance. In a word, the performance of the circuit breaker is limited and the cost is high because the current flows through the tripping assembly.
Therefore, it is expected to propose a circuit breaker to improve the defects in the above-mentioned prior art.

SUMMARY

According to one aspect of the present invention, a circuit breaker is proposed, comprising: a main body having a stationary contact and a movable contact, the movable contact being movable to contact with or separate from the stationary contact; a tripping assembly assembled to the main body, the tripping assembly being movable between a normal position and a trigger position, and the tripping assembly triggering the movable contact to separate from the stationary contact when the tripping assembly moves from the normal position to the trigger position; wherein, the tripping assembly has a current sensing part which is located near the stationary contact and is configured to be movable based on the current intensity flowing through the stationary contact.
According to this implement, the tripping assembly triggers the trip operation based on the current flowing through the stationary contact of the main body of the circuit breaker sensed by the current sensing part, instead of triggering the trip operation based on the current flowing through the tripping assembly as in the prior art. Because no current flows through the tripping assembly, the tripping assembly does not need to have high insulation and high heat resistance to prevent heat damage caused by current, thus improving the trip performance of the circuit breaker and reducing the manufacturing cost of the circuit breaker.
In some implements, the current sensing part is a attracted core, and a static core is arranged near the stationary contact, and the attracted core is movable between a release position wherein the attracted core is separated from the static core and the tripping assembly is in the normal position and a attracted position wherein the attracted core is contacted with the static core and the tripping assembly is in the trigger position.
According to this implement, when the current flowing through the main body is excessive, the static core near the stationary contact generates a large magnetic field to attract the attracted core to move towards the static core, thus completing the trigger of the tripping assembly.
In some aspects, the tripping assembly further comprises an elastic component comprising a first end fixed and a second end opposite to the first end connected to the tripping assembly to bias the tripping assembly toward the normal position.
According to this implement, when the current flowing through the main body is not large enough, the tripping assembly is in a normal position under the bias of the elastic component without triggering the circuit breaker to open.
In some aspects, the elastic component may be a torsion spring.
In some aspects, the tripping assembly may further comprise an adjusting component with a plurality of grooves, and the first end of the torsion spring is selectively fixed to one of the grooves to adjust the included angle between the first end and the second end of the torsion spring.
According to this implement, the force applied by the torsion spring to the tripping assembly can be adjusted by adjusting the initial bias degree of the torsion spring, so as to adjust the threshold of magnetic field force between the static core and the attracted core that can overcome the force applied by the torsion spring to the tripping assembly so as to move the tripping assembly, adjusting the current intensity threshold that can trigger the circuit breaker to be disconnected.
In some aspects, the tripping assembly can be designed such that when the current flowing through the main body is greater than a predetermined threshold, the attracted core moves to contact with the static core against the force of the torsion spring.
According to this implement, when the current flowing through the main body is greater than the predetermined threshold, the tripping assembly is triggered under the action of attracting the core to open the circuit breaker.
In some implements, the tripping assembly may further include a pull lever, the first end of which is connected to the attracted core and is drivable by the attracted core to move linearly;
a tripping lever, the first end of which is connected to the second end of the pull lever opposite to its first end and is drivable to rotate by the pull lever, and the second end of which opposite to its first end is coupled to the movable contact to drive the movable contact to move.
In some implements, the main body can also include a transmission assembly, and the transmission assembly is respectively connected with the second end of the tripping lever and the movable contact, so that the movement of the tripping lever is able to drive the movable contact to move.
In some implements, the main body can include two cavities separated by an intermediate partition, and a stationary contact being respectively arranged in the two cavities, and the tripping assembly comprises two attracted cores, which are attracted or released by the static cores near the corresponding stationary contacts.
In some implements, a limiting part can be arranged in the tripping assembly and is configured such that at least a part of the static core is sandwiched between the limiting part and the stationary contact to fix the static core.
According to this implement, during the operation of the tripping assembly, the limiting part can keep the static core and the attracted core aligned all the time to ensure the attracted between the static core and the attracted core.
In some implements, the intermediate partition can be provided with an mounting hole, through which the tripping assembly is assembled to the main body.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 shows a schematic side view of a circuit breaker according to an embodiment of the present invention;
Fig. 2 shows a schematic top view of a circuit breaker according to an embodiment of the present invention;
Fig. 3 shows a schematic front view of a circuit breaker according to an embodiment of the present invention;
Fig. 4 shows a schematic diagram of a main body of a circuit breaker according to an embodiment of the present invention;
Fig. 5 shows a schematic diagram of a tripping assembly of a circuit breaker according to an embodiment of the present invention.

Reference numeral list:

10 circuit breaker
100 main body
110 stationary contact
120 static core
130 transmission assembly
140 cavity
150 intermediate partition
152 mounting hole
160 limiting part
200 tripping assembly
210 attracted core
220 elastic component, torsion spring
222 first end
224 second end
230 adjusting component
232 first groove
234 second groove
236 third groove
240 pull lever
242 first end
244 second end
250 tripping lever
252 first end
254 second end
260 assembly hole

DETAILED DESCRIPTION

In order to make the purpose, implement and advantages of the technical implement of the present invention more clear, the technical implement of the embodiment of the present invention will be described clearly and completely with the attached drawings of specific embodiments of the present invention. Unless otherwise specified, the terms used herein have the ordinary meaning in the art. Like reference numerals in the drawings represent like components.
Figs. 1, 2 and 3 respectively show a schematic side view, a schematic top view and a schematic front view of a circuit breaker 10 according to an embodiment of the present invention. The circuit breaker 10 is mainly composed of a main body 100 and a tripping assembly 200. The main body 100 has a stationary contact 110 and a movable contact (not shown). The movable contact can move to contact with or separate from the stationary contact 110 to make the circuit breaker 10 in a closed state or an open state, respectively. A tripping assembly 200 is assembled to the main body 100, and the tripping assembly 200 triggers the circuit breaker 10 to switch from the closed state to the open state in response to the current overload (for example, exceeding a predetermined current intensity threshold) in the main body 100. Specifically, the tripping assembly 200 can move between a normal position (corresponding to the normal operation of the circuit without overload) and a trigger position (corresponding to the abnormal operation of the circuit with overload having been occurred). When an unexpected event causes the current in the circuit to overload, the tripping assembly 200 moves from the normal position to the trigger position to trigger the movable contact to separate from the stationary contact 110, thereby opening the circuit to protect the circuit.
In the traditional circuit breaker, the tripping assembly senses the current intensity in the circuit through the current flowing through it, but the current flowing through the tripping assembly requires high electrical insulation performance. And because the current flowing through the tripping assembly will generate heat in the tripping assembly, the tripping assembly also requires high heat resistance. They are not conducive to the tripping performance and cost of the circuit breaker. For this reason, in the circuit breaker 10 of the present invention, no current flows through the tripping assembly 200. In order to realize the tripping function, the tripping assembly 200 needs to have the ability to sense the magnitude of current flowing through the circuit breaker 10. In the case that no current flows through the tripping assembly 200, the present invention senses the magnitude of current flowing through the main body 100 of the circuit breaker 10 by arranging the attracted core 210 in the tripping assembly 200, as detailed below.
A static core 120 is arranged near the stationary contact 110, which can generate a magnetic field related (for example, in direct proportion) to the current intensity flowing through the main body 100 of the circuit breaker 10. The static core 120 is used to attract the attracted core 210 in the tripping assembly 200 to move toward the static core 120. The magnitude of the attraction between the static core 120 and the attracted core 210 is related (for example, in direct proportion) to the current intensity flowing through the main body 100 of the circuit breaker 10.
When the current flowing through the main body 100 of the circuit breaker 10 does not increase abnormally, the static core 120 does not generate enough large magnetic field to attract the attracted core 210 to move toward the static core 120. At this time, the attracted core 210 is in the release position (the attracted core 210 is separated from the static core 120) and the tripping assembly 200 is in the normal position.
When the current intensity flowing through the main body 100 of the circuit breaker 10 is large enough, the magnetic field generated by the static core 120 is large enough to attract the attracted core 210 to move towards the static core 120. At this time, the attracted core 210 is in the attracted position (the attracted core 210 is in contact with the static core 120) and the tripping assembly 200 is triggered (the specific triggering process is described in detail below).
Preferably, the tripping assembly 200 may further include an elastic component 220 including a first end 222 fixed and a second end 224 opposite to the first end 222 connected to the tripping assembly 200 (for example, connected to a pull lever 240 described below) to bias the tripping assembly 200 toward a normal position. The biasing force of the elastic component 220 opposes the attraction between the static core 120 and the attracted core 210.
When the current flowing through the main body 100 of the circuit breaker 10 is not large enough, the attractive force between the static core 120 and the attracted core 210 is not enough to overcome the biasing force of the elastic component 220 to move the attracted core 210 toward the static core 120. At this time, the tripping assembly 200 is in a normal position under the biasing force of the elastic component 220 without triggering the circuit breaker 10 to be disconnected.
When the current flowing through the main body 100 of the circuit breaker 10 is large enough, the attractive force between the static core 120 and the attracted core 210 is enough to overcome the biasing force of the elastic component 220 to move the attracted core 210 toward the static core 120. At this time, the tripping assembly 200 moves from the normal position to the trigger position under the attractive force between the attracted core 210 and the static core 120, thus triggering the circuit breaker 10 to be disconnected.
Alternatively, the elastic component 220 may be a torsion spring. It should be understood that the present invention is not intended to limit the specific type of the elastic component. The elastic component 220 may be any other suitable device capable of generating a restoring force.
Preferably, the tripping assembly 200 may further include an adjusting component 230 having a plurality of grooves 232, 234 and 236, and the first end 222 of the torsion spring 220 is selectively fixed to one of the grooves 232, 234 and 236 to adjust the included angle between the first end 222 and the second end 224 of the torsion spring 220. By adjusting the initial bias degree of the torsion spring 220, the acting force applied by the torsion spring 220 to the tripping assembly 200 can be adjusted, so as to adjust the threshold magnetic field force between the static core 120 and the attracted core 210 that can overcome the acting force of the torsion spring 220 to move the tripping assembly 200, adjusting the current intensity threshold that can trigger the circuit breaker 10 to open according to different application requirements.
For example, if it is necessary to make the circuit breaker 10 have a low-grade current intensity threshold, the first end 222 of the torsion spring 220 is fixed to the first groove 232. Under this configuration, the included angle between the first end 222 and the second end 224 of the torsion spring 220 is small, and the biasing force generated by the torsion spring 220 is small, so the threshold attracted force between the core 210 and the static core 120 which can overcome the biasing force of the torsion spring 220 to make the core 210 move towards the static core 120 is small so that the threshold current is small.
If it is necessary to make the circuit breaker 10 have a high-grade current intensity threshold, the first end 222 of the torsion spring 220 is fixed to the third groove 236. Under this configuration, the included angle between the first end 222 and the second end 224 of the torsion spring 220 is large, and the biasing force generated by the torsion spring 220 is large, so the threshold attracted force between the core 210 and the static core 120 which can overcome the biasing force of the torsion spring 220 to make the core 210 move towards the static core 120 is large so that the threshold current is large.
Similarly, if it is necessary to make the circuit breaker 10 have a mid-range current intensity threshold (i.e., between high and low grades), the first end 222 of the torsion spring 220 is fixed to the second groove 234. It should be understood that the number of grooves (i.e., the number of gears) is only exemplary, and the adjusting component 230 may also have 2, 4 or any other suitable number of grooves to meet the current threshold adjustment requirements in different application situations.
Optionally, as shown in fig. 5, the tripping assembly 200 may further include a pull lever 240 and a tripping lever 250, and the first end 242 of the pull lever 240 is connected to the attracted core 210 and can be driven by the attracted core 210 to move linearly. The first end 252 of the tripping lever 250 is connected to the second end 244 of the pull lever 240 opposite to the first end 242 and can be driven to rotate by the pull lever 240. The second end 254 of the tripping lever 250 opposite to the first end 252 is coupled to the movable contact to drive the movable contact to move. It should be understood that the term "A coupled to B" means that A is associated with B, and does not necessarily mean that A is directly connected to B. In the situation shown in fig. 1, when the tripping assembly 200 moves from the normal position to the trigger position, the pull lever 240 moves downward toward the static core 120 under the action of the attracted core 210, and the tripping lever 250 rotates clockwise under the action of the pull lever 240 (that is, the first end 252 moves downward and the second end 254 moves upward).
Optionally, as shown in fig. 4, the main body 100 may further include a transmission assembly 130, which is respectively connected with the second end 254 of the tripping lever 250 and the movable contact, so that the movement of the tripping lever 250 can drive the movable contact to move.
Alternatively, the main body 100 may include two cavities 140 separated by an intermediate partition 150 in which one stationary contact 110 is respectively arranged. The tripping assembly 200 includes two attracted cores 210 attracted or released by the static cores 120 near the corresponding stationary contacts 110. During the tripping operation, the two attracted cores 210 pull down two corresponding pull levers 240, respectively, and the two pull levers 240 together actuate a tripping lever 250. It should be understood that the present invention is not intended to limit the number of cavities accommodating the stationary contacts 110, and the main body 100 may also include, for example, three or four or even more cavities accommodating the stationary contacts 110.
Preferably, the tripping assembly 200 can be provided with a limiting part 160 which is configured such that at least a part of the static core 120 is sandwiched between the limiting part 160 and the stationary contact 110 to fix the static core 120. During the movement of the tripping assembly 200, the limiting part 160 can keep the static core 120 and the attracted core 210 aligned at all times to ensure the attracting effects between the static core 120 and the attracted core 210.
In addition, the intermediate partition 150 may be provided with a mounting hole 152 through which the tripping assembly 200 is assembled to the main body 100. For example, the assembly hole 260 on the tripping assembly 200 is aligned with the mounting hole 152, and the tripping assembly 200 is assembled to the main body 100 by passing screws through the assembly hole 260 and the mounting hole 152.
A number of exemplary embodiments of the present invention have been described in detail herein with reference to preferred embodiments. However, those skilled in the art can understand that various variations and modifications can be made to the above specific embodiments without departing from the inventive concept, and various technical features and structures proposed by the present invention can be combined without exceeding the scope of protection of the present invention, which is determined by the appended claims.

Claims

A circuit breaker comprises:
a main body having a stationary contact and a movable contact, the movable contact being movable to contact with or separate from the stationary contact;

a tripping assembly assembled to the main body, the tripping assembly being movable between a normal position and a trigger position, and the tripping assembly triggering the movable contact to separate from the stationary contact when the tripping assembly moves from the normal position to the trigger position;

wherein, the tripping assembly has a current sensing part which is located near the stationary contact and is configured to be movable based on the current intensity flowing through the stationary contact.
The circuit breaker according to claim 1, wherein the current sensing part is a attracted core, and a static core is arranged near the stationary contact, and the attracted core is movable between a release position wherein the attracted core is separated from the static core and the tripping assembly is in the normal position and a attracted position wherein the attracted core is contacted with the static core and the tripping assembly is in the trigger position.
The circuit breaker according to claim 2, wherein the tripping assembly further comprises an elastic component comprising a first end fixed and a second end opposite to the first end connected to the tripping assembly to bias the tripping assembly toward the normal position.
The circuit breaker according to claim 3, wherein the elastic component is a torsion spring.
The circuit breaker according to claim 4, wherein the tripping assembly further comprises an adjusting component with a plurality of grooves, and the first end of the torsion spring is selectively fixed to one of the grooves to adjust the included angle between the first end and the second end of the torsion spring.
The circuit breaker according to one of claims 2-5, wherein the tripping assembly is designed such that when the current flowing through the main body is greater than a predetermined threshold, the attracted core moves to contact with the static core against the force of the torsion spring.
The circuit breaker according to one of claims 2-5, wherein the tripping assembly further comprises:
a pull lever, the first end of which is connected to the attracted core and is drivable by the attracted core to move linearly;

a tripping lever, the first end of which is connected to the second end of the pull lever opposite to its first end and is drivable to rotate by the pull lever, and the second end of which opposite to its first end is coupled to the movable contact to drive the movable contact to move.
The circuit breaker according to claim 7, wherein the main body further comprises a transmission assembly, and the transmission assembly is respectively connected with the second end of the tripping lever and the movable contact, so that the movement of the tripping lever is able to drive the movable contact to move.
The circuit breaker according to any one of claims 2 to 5, wherein the main body comprises two cavities separated by an intermediate partition, and a stationary contact being respectively arranged in the two cavities, and the tripping assembly comprises two attracted cores, which are attracted or released by the static cores near the corresponding stationary contacts.
The circuit breaker according to claim 9, wherein a limiting part is arranged in the tripping assembly and is configured such that at least a part of the static core is sandwiched between the limiting part and the stationary contact to fix the static core.
The circuit breaker according to claim 9, wherein the intermediate partition is provided with a mounting hole, through which the tripping assembly is assembled to the main body.